A taggle system and walk-over-weigher have now been commissioned, and extensive soil sampling for sequestered carbon has been undertaken at DeGrey Station in the Pilbara.
This work is to complement the benchmark biomass sampling completed earlier this year, and as outlined in the June edition of eNews, is part of a large, multi-faceted cattle grazing trial being undertaken by the Bettini Family on their coastal northern Pilbara station, east of Port Hedland.
Rangelands NRM Senior Rangelands Scientist Dr Peter Russell said this commercial-scale project is a trial of innovative ways to manage stock, integrated with an ecological approach to management of the landscape.
“Within the 50,000 ha trial paddock, key management elements such as rest-based seasonal rotation, self-shepherding, and frequent pasture (feed) budgeting, landscape rehydration and proactive fire control will be developed and tested over several years,” he said.
The diagram represents three key areas of management (landscape, stock and pasture), together with the main non-financial aspects and indicators being monitored and studied.
“As the management changes take effect, it is expected that changes in a number of these aspects and indicators will become evident, although some will change quicker than others, and some may not change over the course of the trial,” Dr Russell said.
Soil sampling took place at the same plots where the earlier benchmark biomass (pasture) sampling was undertaken, and together, will allow estimation of pre-trial above- and below-ground sequestered carbon stocks.
The soil coring was ably done by David Blood (ecologist) and Bill Currans (Executive Officer, DeGrey LCDC) using a portable, hand-held Christie drilling machine.
At each plot, five soil cores, to 300mm depth, were taken. Over a period of six days, 58 plots were sampled at a daily average of over nine plots (45 cores) with the best day seeing 14 plots completed. All soil cores have now been delivered to the ChemCentre, Perth for laboratory analysis.
Dr Russell said field data compilation and statistical analysis of both the biomass and soil data will be undertaken over the next couple of months.
“It is anticipated that results of the biomass and soil sampling, along with studies done by others, will be presented at a LCDC field day or project launch at DeGrey Station in early 2015, after the country has dried out sufficiently following the wet season,” he said.
The carbon work at DeGrey is funded by Royalties for Regions and is a continuation of our Carbon Awareness Project under which similar work has been undertaken at other stations in the Murchison region.
This is an exciting, innovative, commercial-scale project being driven by the Bettini Family.
“Their incorporation of new technologies such as grazing pattern mapping by taggle and automated stock data capture through walk-over-weighing, combined with an ecological approach to managing the landscape, is a new and bold trial that if successful, is likely to strongly influence grazing management throughout the DeGrey River catchment and more broadly in other Australian grasslands,” Dr Russell said.
Diagram showing three key management areas and associated change indicators to be measured and studied in the DeGrey Grazing Trial.
Bill Currans operating the Christie soil coring machine at DeGrey Station, 2nd November 2014. Photo by D. Blood.